用nginx正向代理https网站

1. 缘起

最近碰到了一个麻烦事情，就是公司的centos测试服务器放在内网环境，而且不能直接上外网，导致无法通过yum安装软件，非常捉急。

幸好，内网还是有可以可以访问外网的机器，所以就想到应该可以利用nginx搭建一个代理服务器，然后centos通过这个nginx来访问外网。当然，如果只是代理http还是很简单的，而要代理https还是需要稍费周折，因为nginx本身不能部署被代理的网站的证书，不能部署成https终结点来，因此与被代理客户端之间不能用ssl协议通讯，因此需要通过http协议中的CONNECT请求打通和外网的连接，然后客户端到nginx走明文，nginx到外网走https协议。这里需要用到ngx_http_proxy_connect_module模块来实现CONNECT的代理功能。

2. 部署nginx

步骤1：从nginx官网下载nginx源码包。
步骤2：因为nginx原生是不支持CONNECT请求的，需要安装一个扩展插件，即ngx_http_proxy_connect_module，从github下载ngx_http_proxy_connect_module，另外还要下载一个nginx内核补丁。
步骤3：解压nginx源码包，进入nginx源码目录，创建modules目录（mkdir modules)。
步骤4：将ngx_http_proxy_connect_module源码目录放到modules目录中。
步骤5：将nginx内核补丁放到nginx源码目录，姑且名字叫p1.patch
步骤6：在nginx源码目录，执行以下命令给nginx内核打上补丁：
```
  patch -p 1 < p1.patch
```
步骤7：编译nginx，这里假设nginx安装到/opt/nginx目录中（在编译前确认pcre、zlib、openssl的库是否已经正常安装），编译命令如下：

./configure --prefix=/opt/nginx --with-http_ssl_module -add-module=./modules/ngx_http_proxy_connect_module
make & make install

步骤8：配置nginx
配置文件如下：

#user nobody;
worker_processes 1;

#error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;

#pid logs/nginx.pid;

events {
worker_connections 1024;
}

http {
include mime.types;
default_type application/octet-stream;

  #log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
  #                  '$status $body_bytes_sent "$http_referer" '
  #                  '"$http_user_agent" "$http_x_forwarded_for"';

  #access_log  logs/access.log  main;

  sendfile        on;
  keepalive_timeout  65;


server {
      # 代理端口
  	listen 8080;
      server_name  localhost;
      
      # 解析被代理网站域名的dns服务器，根据实际情况自行配置
      resolver  114.114.114.114;
      
      # 开启proxy connect功能
      proxy_connect;
      
      # 设置允许代理的目标端口为443,即https的默认端口
      proxy_connect_allow 443 80;

      location / { 
      
          # 正向代理配置，根据请求地址自动解析出目标网站地址并进行代理
          proxy_pass $scheme://$host$request_uri;
          
          # 发送到被代理网站的请求需要添加host头
          proxy_set_header Host $http_host;
      
  		proxy_buffers 256 4k; 
          proxy_max_temp_file_size 0;
          proxy_connect_timeout 30; 
      }
  }

}

以上配置完成后，通过nginx的8080端口，既可以代理普通http的请求，也可以代理https的请求。

步骤9：启动nginx
执行/opt/nginx/sbin/nginx，启动nginx

3. 测试

3.1 http测试

curl "http://www.baidu.com/" -x 127.0.0.1:8080 -v

响应内容：

*   Trying 127.0.0.1:8080...
* Connected to (nil) (127.0.0.1) port 8080 (#0)
> GET http://www.baidu.com/ HTTP/1.1
> Host: www.baidu.com
> User-Agent: curl/7.81.0
> Accept: */*
> Proxy-Connection: Keep-Alive
> 
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Server: nginx/1.24.0
< Date: Fri, 23 Feb 2024 09:08:01 GMT
< Content-Type: text/html
< Content-Length: 2381
< Connection: keep-alive
< Accept-Ranges: bytes
< Cache-Control: private, no-cache, no-store, proxy-revalidate, no-transform
< Etag: "588604eb-94d"
< Last-Modified: Mon, 23 Jan 2017 13:28:11 GMT
< Pragma: no-cache
< Set-Cookie: BDORZ=27315; max-age=86400; domain=.baidu.com; path=/
< 
<!DOCTYPE html>
<!--STATUS OK--><html> <head><meta http-equiv=content-type content=text/html;charset=utf-8><meta http-equiv=X-UA-Compatible content=IE=Edge><meta content=always name=referrer><link rel=stylesheet type=text/css href=http://s1.bdstatic.com/r/www/cache/bdorz/baidu.min.css><title>百度一下，你就知道</title></head> <body link=#0000cc> <div id=wrapper> <div id=head> <div class=head_wrapper> <div class=s_form> <div class=s_form_wrapper> <div id=lg> <img hidefocus=true src=//www.baidu.com/img/bd_logo1.png width=270 height=129> </div> <form id=form name=f action=//www.baidu.com/s class=fm> <input type=hidden name=bdorz_come value=1> <input type=hidden name=ie value=utf-8> <input type=hidden name=f value=8> <input type=hidden name=rsv_bp value=1> <input type=hidden name=rsv_idx value=1> <input type=hidden name=tn value=baidu><span class="bg s_ipt_wr"><input id=kw name=wd class=s_ipt value maxlength=255 autocomplete=off autofocus></span><span class="bg s_btn_wr"><input type=submit id=su value=百度一下 class="bg s_btn"></span> </form> </div> </div> <div id=u1> <a href=http://news.baidu.com name=tj_trnews class=mnav>新闻</a> <a href=http://www.hao123.com name=tj_trhao123 class=mnav>hao123</a> <a href=http://map.baidu.com name=tj_trmap class=mnav>地图</a> <a href=http://v.baidu.com name=tj_trvideo class=mnav>视频</a> <a href=http://tieba.baidu.com name=tj_trtieba class=mnav>贴吧</a> <noscript> <a href=http://www.baidu.com/bdorz/login.gif?login&amp;tpl=mn&amp;u=http%3A%2F%2Fwww.baidu.com%2f%3fbdorz_come%3d1 name=tj_login class=lb>登录</a> </noscript> <script>document.write('<a href="http://www.baidu.com/bdorz/login.gif?login&tpl=mn&u='+ encodeURIComponent(window.location.href+ (window.location.search === "" ? "?" : "&")+ "bdorz_come=1")+ '" name="tj_login" class="lb">登录</a>');</script> <a href=//www.baidu.com/more/ name=tj_briicon class=bri style="display: block;">更多产品</a> </div> </div> </div> <div id=ftCon> <div id=ftConw> <p id=lh> <a href=http://home.baidu.com>关于百度</a> <a href=http://ir.baidu.com>About Baidu</a> </p> <p id=cp>&copy;2017&nbsp;Baidu&nbsp;<a href=http://www.baidu.com/duty/>使用百度前必读</a>&nbsp; <a href=http://jianyi.baidu.com/ class=cp-feedback>意见反馈</a>&nbsp;京ICP证030173号&nbsp; <img src=//www.baidu.com/img/gs.gif> </p> </div> </div> </div> </body> </html>

通过以上的输出可以看到http代理是没有通过CONNECT请求进行连接的，响应正常。

3.2 https测试

 curl "https://www.baidu.com/" -x 127.0.0.1:8080 -v

*   Trying 127.0.0.1:8080...
* Connected to (nil) (127.0.0.1) port 8080 (#0)
* allocate connect buffer!
* Establish HTTP proxy tunnel to www.baidu.com:443
> CONNECT www.baidu.com:443 HTTP/1.1
> Host: www.baidu.com:443
> User-Agent: curl/7.81.0
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 200 Connection Established
< Proxy-agent: nginx
< 
* Proxy replied 200 to CONNECT request
* CONNECT phase completed!
* ALPN, offering h2
* ALPN, offering http/1.1
*  CAfile: /etc/ssl/certs/ca-certificates.crt
*  CApath: /etc/ssl/certs
* TLSv1.0 (OUT), TLS header, Certificate Status (22):
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS header, Finished (20):
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS header, Finished (20):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
* ALPN, server accepted to use http/1.1
* Server certificate:
*  subject: C=CN; ST=beijing; L=beijing; O=Beijing Baidu Netcom Science Technology Co., Ltd; CN=baidu.com
*  start date: Jul  6 01:51:06 2023 GMT
*  expire date: Aug  6 01:51:05 2024 GMT
*  subjectAltName: host "www.baidu.com" matched cert's "*.baidu.com"
*  issuer: C=BE; O=GlobalSign nv-sa; CN=GlobalSign RSA OV SSL CA 2018
*  SSL certificate verify ok.
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
> GET / HTTP/1.1
> Host: www.baidu.com
> User-Agent: curl/7.81.0
> Accept: */*
> 
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Accept-Ranges: bytes
< Cache-Control: private, no-cache, no-store, proxy-revalidate, no-transform
< Connection: keep-alive
< Content-Length: 2443
< Content-Type: text/html
< Date: Fri, 23 Feb 2024 09:11:25 GMT
< Etag: "58860410-98b"
< Last-Modified: Mon, 23 Jan 2017 13:24:32 GMT
< Pragma: no-cache
< Server: bfe/1.0.8.18
< Set-Cookie: BDORZ=27315; max-age=86400; domain=.baidu.com; path=/
< 
<!DOCTYPE html>
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* TLSv1.2 (IN), TLS header, Supplemental data (23):
<!--STATUS OK--><html> <head><meta http-equiv=content-type content=text/html;charset=utf-8><meta http-equiv=X-UA-Compatible content=IE=Edge><meta content=always name=referrer><link rel=stylesheet type=text/css href=https://ss1.bdstatic.com/5eN1bjq8AAUYm2zgoY3K/r/www/cache/bdorz/baidu.min.css><title>百度一下，你就知道</title></head> <body link=#0000cc> <div id=wrapper> <div id=head> <div class=head_wrapper> <div class=s_form> <div class=s_form_wrapper> <div id=lg> <img hidefocus=true src=//www.baidu.com/img/bd_logo1.png width=270 height=129> </div> <form id=form name=f action=//www.baidu.com/s class=fm> <input type=hidden name=bdorz_come value=1> <input type=hidden name=ie value=utf-8> <input type=hidden name=f value=8> <input type=hidden name=rsv_bp value=1> <input type=hidden name=rsv_idx value=1> <input type=hidden name=tn value=baidu><span class="bg s_ipt_wr"><input id=kw name=wd class=s_ipt value maxlength=255 autocomplete=off autofocus=autofocus></span><span class="bg s_btn_wr"><input type=submit id=su value=百度一下 class="bg s_btn" autofocus></span> </form> </div> </div> <div id=u1> <a href=http://news.baidu.com name=tj_trnews class=mnav>新闻</a> <a href=https://www.hao123.com name=tj_trhao123 class=mnav>hao123</a> <a href=http://map.baidu.com name=tj_trmap class=mnav>地图</a> <a href=http://v.baidu.com name=tj_trvideo class=mnav>视频</a> <a href=http://tieba.baidu.com name=tj_trtieba class=mnav>贴吧</a> <noscript> <a href=http://www.baidu.com/bdorz/login.gif?login&amp;tpl=mn&amp;u=http%3A%2F%2Fwww.baidu.com%2f%3fbdorz_come%3d1 name=tj_login class=lb>登录</a> </noscript> <script>document.write('<a href="http://www.baidu.com/bdorz/login.gif?login&tpl=mn&u='+ encodeURIComponent(window.location.href+ (window.location.search === "" ? "?" : "&")+ "bdorz_come=1")+ '" name="tj_login" class="lb">登录</a>');
                </script> <a href=//www.baidu.com/more/ name=tj_briicon class=bri style="display: block;">更多产品</a> </div> </div> </div> <div id=ftCon> <div id=ftConw> <p id=lh> <a href=http://home.baidu.com>关于百度</a> <a href=http://ir.baidu.com>About Baidu</a> </p> <p id=cp>&copy;2017&nbsp;Baidu&nbsp;<a href=http://www.baidu.com/duty/>使用百度前必读</a>&nbsp; <a href=http://jianyi.baidu.com/ class=cp-feedback>意见反馈</a>&nbsp;京ICP证030173号&nbsp; <img src=//www.baidu.com/img/gs.gif> </p> </div> </div> </div> </body> </html>

通过以上的输出可以看到https代理是通过CONNECT请求进行连接的，中间有发生ssl的握手过程，也已经正常进行了响应。

4 给centos设置代理访问外网

给centos服务器设置两个http_proxy和https_proxy环境变量，假设nginx服务器的ip为192.168.0.1，那么在命令行执行以下两条命令，即：

text 复制代码

export http_proxy="http://192.168.0.1:8080"
export https_proxy="https://192.168.0.1:8080"

然后就可以顺畅地进行yum了。当然，如果可以的话，就将以上两条命令配置到bash.rc中，这样子免得每次登录都需要敲命令。